[src/trunk]: src/usr.bin/xlint/lint1 lint: distinguish between read and write...

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/1c66706a8af4
branches:  trunk
changeset: 953951:1c66706a8af4
user:      rillig <rillig%NetBSD.org@localhost>
date:      Thu Mar 25 21:36:41 2021 +0000

description:
lint: distinguish between read and write access to initstk

There are far too many places that modify the top element of the
initializer stack.  Each of these places should get its own logging, as
long as the code is still complicated.  These places are now clearly
marked with initstk_lvalue.

No functional change.

diffstat:

 usr.bin/xlint/lint1/init.c |  58 ++++++++++++++++++++++++++-------------------
 1 files changed, 33 insertions(+), 25 deletions(-)

diffs (195 lines):

diff -r c06338506841 -r 1c66706a8af4 usr.bin/xlint/lint1/init.c
--- a/usr.bin/xlint/lint1/init.c        Thu Mar 25 21:07:52 2021 +0000
+++ b/usr.bin/xlint/lint1/init.c        Thu Mar 25 21:36:41 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: init.c,v 1.128 2021/03/25 21:07:52 rillig Exp $        */
+/*     $NetBSD: init.c,v 1.129 2021/03/25 21:36:41 rillig Exp $        */
 
 /*
  * Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: init.c,v 1.128 2021/03/25 21:07:52 rillig Exp $");
+__RCSID("$NetBSD: init.c,v 1.129 2021/03/25 21:36:41 rillig Exp $");
 #endif
 
 #include <stdlib.h>
@@ -294,8 +294,15 @@
        return *current_designation_mod();
 }
 
+static const initstack_element *
+current_initstk(void)
+{
+       lint_assert(init != NULL);
+       return init->initstk;
+}
+
 static initstack_element **
-current_initstk(void)
+current_initstk_lvalue(void)
 {
        lint_assert(init != NULL);
        return &init->initstk;
@@ -316,7 +323,8 @@
 
 #define initerr                (*current_initerr())
 #define initsym                (*current_initsym())
-#define initstk                (*current_initstk())
+#define initstk                (current_initstk())
+#define initstk_lvalue (*current_initstk_lvalue())
 
 #ifndef DEBUG
 
@@ -563,7 +571,7 @@
                initsym->s_type = duptyp(initsym->s_type);
        /* TODO: does 'duptyp' create a memory leak? */
 
-       istk = initstk = xcalloc(1, sizeof (initstack_element));
+       istk = initstk_lvalue = xcalloc(1, sizeof (initstack_element));
        istk->i_subt = initsym->s_type;
        istk->i_remaining = 1;
 
@@ -575,7 +583,7 @@
 static void
 initstack_pop_item_named_member(void)
 {
-       initstack_element *istk = initstk;
+       initstack_element *istk = initstk_lvalue;
        sym_t *m;
 
        /*
@@ -621,7 +629,7 @@
 static void
 initstack_pop_item_unnamed(void)
 {
-       initstack_element *istk = initstk;
+       initstack_element *istk = initstk_lvalue;
        sym_t *m;
 
        /*
@@ -650,14 +658,14 @@
 
        debug_enter();
 
-       istk = initstk;
+       istk = initstk_lvalue;
        debug_indent();
        debug_printf("popping: ");
        debug_initstack_element(istk);
 
-       initstk = istk->i_enclosing;
+       initstk_lvalue = istk->i_enclosing;
        free(istk);
-       istk = initstk;
+       istk = initstk_lvalue;
        lint_assert(istk != NULL);
 
        istk->i_remaining--;
@@ -714,7 +722,7 @@
 static void
 extend_if_array_of_unknown_size(void)
 {
-       initstack_element *istk = initstk;
+       initstack_element *istk = initstk_lvalue;
 
        if (istk->i_remaining != 0)
                return;
@@ -740,7 +748,7 @@
 static void
 initstack_push_array(void)
 {
-       initstack_element *const istk = initstk;
+       initstack_element *istk = initstk_lvalue;
 
        if (istk->i_enclosing->i_seen_named_member) {
                istk->i_brace = true;
@@ -775,7 +783,7 @@
         * TODO: remove unnecessary 'const' for variables in functions that
         * fit on a single screen.  Keep it for larger functions.
         */
-       initstack_element *const istk = initstk;
+       initstack_element *istk = initstk_lvalue;
        int cnt;
        sym_t *m;
 
@@ -859,17 +867,17 @@
 
        extend_if_array_of_unknown_size();
 
-       istk = initstk;
+       istk = initstk_lvalue;
        lint_assert(istk->i_remaining > 0);
        lint_assert(istk->i_type == NULL || !is_scalar(istk->i_type->t_tspec));
 
-       initstk = xcalloc(1, sizeof (initstack_element));
-       initstk->i_enclosing = istk;
-       initstk->i_type = istk->i_subt;
-       lint_assert(initstk->i_type->t_tspec != FUNC);
+       initstk_lvalue = xcalloc(1, sizeof (initstack_element));
+       initstk_lvalue->i_enclosing = istk;
+       initstk_lvalue->i_type = istk->i_subt;
+       lint_assert(initstk_lvalue->i_type->t_tspec != FUNC);
 
 again:
-       istk = initstk;
+       istk = initstk_lvalue;
 
        debug_step("expecting type '%s'", type_name(istk->i_type));
        lint_assert(istk->i_type != NULL);
@@ -901,7 +909,7 @@
                        /* TODO: extract this into end_initializer_level */
                        inxt = initstk->i_enclosing;
                        free(istk);
-                       initstk = inxt;
+                       initstk_lvalue = inxt;
                        goto again;
                }
                /* The initialization stack now expects a single scalar. */
@@ -962,7 +970,7 @@
        if (!initerr)
                initstack_push();
        if (!initerr) {
-               initstk->i_brace = true;
+               initstk_lvalue->i_brace = true;
                debug_designation();
                debug_step("expecting type '%s'",
                    type_name(initstk->i_type != NULL ? initstk->i_type
@@ -989,7 +997,7 @@
                check_too_many_initializers();
 
        while (!initerr) {
-               initstack_element *istk = initstk;
+               initstack_element *istk = initstk_lvalue;
 
                if (tn->tn_type->t_tspec == STRUCT &&
                    istk->i_type == tn->tn_type &&
@@ -1188,7 +1196,7 @@
        if (initerr || tn == NULL)
                goto done_initstack;
 
-       initstk->i_remaining--;
+       initstk_lvalue->i_remaining--;
        debug_step("%d elements remaining", initstk->i_remaining);
 
        check_init_expr(tn, sclass);
@@ -1215,7 +1223,7 @@
        debug_enter();
        debug_initstack();
 
-       istk = initstk;
+       istk = initstk_lvalue;
        strg = tn->tn_string;
 
        /*
@@ -1235,7 +1243,7 @@
 
                /* Put the array at top of stack */
                initstack_push();
-               istk = initstk;
+               istk = initstk_lvalue;
 
 
                /* TODO: what if both i_type and i_subt are ARRAY? */